Asymmetric Michael Addition of Cyclohexanone or Cyclopentanone to Chalcones Catalyzed by an<scp>L</scp>-Proline-Based Organic Phosphane
作者:Lingyan Liu、Yunna Zhu、Kaimeng Huang、Weixing Chang、Jing Li
DOI:10.1002/ejoc.201201609
日期:2013.5
An organophosphane catalyst derived from L-proline was shown to be a very effective catalyst for asymmetricMichaeladdition reactions of various chalcones to cyclic ketones including both cyclohexanone and cyclopentanone. The corresponding adducts could be obtained in high yields (up to 91 %) and with excellent enantioselectivities (up to 99 % ee) and diastereomeric ratios (up to >99:1). A possible
Highly enantioselective Michael addition of cyclic ketones to chalcones catalyzed by pyrrolidine-based imides
作者:Hong-Yu Xie、Shu-Rong Ban、Ju-Na Liu、Qing-Shan Li
DOI:10.1016/j.tetlet.2012.05.106
日期:2012.7
An efficient procedure for asymmetric Michaeladdition reaction of cyclic ketones with low activated chalcones catalyzed by pyrrolidine-based phthalimide and 1,8-Naphthalimide catalysts was developed. The corresponding products were obtained in high yields with high diastereoselectivities (up to 99:1 dr) and high enantioselectivities (up to 96% ee) under mild conditions.
Direct asymmetric Michael addition of ketones to chalcones catalyzed by a hydroxyphthalimide derived triazole–pyrrolidine
作者:Togapur Pavan Kumar、Mohammad Abdul Sattar、Vanka Uma Maheshwara Sarma
DOI:10.1016/j.tetasy.2013.11.002
日期:2013.12
An efficient protocol for the enantioselective Michael additions of ketones to chalcones catalyzed by a hydroxyphthalimide linked triazole-pyrrolidine derivative has been developed. The corresponding products, 1,5-dicarbonyl compounds, were obtained in good yields with high levels of stereoselectivities under mild reaction conditions employing benzoic acid as an additive. (C) 2013 Elsevier Ltd. All rights reserved.
A chiral benzoylthiourea–pyrrolidine catalyst for the highly enantioselective Michael addition of ketones to chalcones
作者:Shu-rong Ban、Xi-xia Zhu、Zhi-ping Zhang、Qing-shan Li
DOI:10.1016/j.bmcl.2014.04.005
日期:2014.6
A benzoylthiourea–pyrrolidine catalyst was developed for the asymmetric Michaeladdition of ketones to chalcones. The corresponding products were obtained in high yields with high level of diastereoselectivities (up to 99:1 dr) and high level of enantioselectivities (up to 94% ee) under mild conditions.